Experts say report about Worcester drivers misses mark

WORCESTER — On Tuesday morning, social media was abuzz with tweets and posts claiming Worcester drivers are the worst in the country.

Traditional media outlets from Boston television stations to telegram.com dutifully passed along the findings of a report claiming to show that Worcester is tops in bad driving.

Just about everywhere you go, people take a kind of perverse civic pride in claiming to have the nation's worst drivers. But don't take a victory lap through Kelley Square just yet, Worcester.

The report succeeded in getting its sponsor, Allstate Insurance Co., a lot of free press, but local statistical experts point out that the study doesn't provide information about the ability of drivers in Worcester or anywhere else.

Allstate titled its ranking "America's Best Drivers Report," but it actually should have been labeled something like "Property Damage Claim Frequency By Location Without Respect to the Residence of Drivers or Severity of Accidents, According to Only One Insurance Company's Limited Claims Experience," experts said.

Worcester State University mathematician Richard Bisk, who teaches a class in using mathematics to model real-world situations, noted that the Allstate rankings are based on the location of accidents — not where the driver lives.

"I would wonder how many of the accidents occur during commuting hours. It's not necessarily even drivers from a particular city," Mr. Bisk said. "Calling Worcester drivers the worst is meaningless if your data counts people who don't live in Worcester."

Statistician Zheyang Wu, an assistant professor of mathematics at Worcester Polytechnic Institute, agreed the report doesn't present enough data to draw any conclusions about the drivers of a particular location.

The report jumps a logical gap by assuming a correlation between locations of accidents and the behavior of drivers who live in that place, Mr. Wu said.

Even if you granted the correlation without any evidence to support it, he added, the report fails to establish a causal link between the accidents and allegedly bad driving behavior.

In other words, drivers from a certain place might get in more accidents for a host of reasons that have nothing to do with their skill or temperament behind the wheel.

"If we have a lot of accidents happening in Worcester, that might be because we have bad road conditions here. Also, the winter is severe, and that could contribute to a high frequency of accidents. It's not necessarily due to bad driving," Mr. Wu said. "The causality issue is something that's very difficult to establish."

Worcester State's Mr. Bisk also doubts a ranking of bad drivers could be meaningful without taking into consideration the severity of crashes. The worst drivers are liable to cause a lot of carnage, he reasoned.

As it happens, the National Highway Traffic Safety Administration collects data on fatal car crashes by city.

Worcester is far from the worst by this measure with an annual rate of slightly more than two crash deaths per 100,000 in population.

Compare that to annual rates of more than six fatalities per 100,000 residents in Augusta, Georgia, and nearly six in Fort Lauderdale, Florida, neither of which has to deal with much snow in the winter. In fact, more than three dozen American cities reported motor vehicle crash death rates higher than Worcester's, according to the NHTSA's latest data.

And then there's the question of whether Allstate's internal claims experience data even represents the industry as a whole.